This shape is very similar to a few used by Loetz in the 1920s and 1930s, but this piece has a cut and polished rim and no pontil (vs. the Loetz with fire-polished rims), so the maker is most likely some contemporary of Loetz - Rückl, perhaps - maybe made for a retailer such as Hosch or Palda. Crystal encased in green with three facet cut windowpanes. Underneath each is a small crystal ball foot. Definitely Czech, definitely deco period, and most definitely a cool little piece - just under 4" tall and about 5" across the top.